The present invention relates to an apparatus for machining, milling or cutting a plurality of workpieces, using only one operator, where each workpiece is on one of a plurality of independent machining assemblies.
Indexing, rotary plates carrying parts past a plurality of different machining assemblies at stations around the plate are known. The workpieces that are placed on and carried by the rotating plate are indexed, and at each indexed station the work piece has an operation performed so a part is machined completely during a full revolution of the indexing plate.
U.S. Pat. No. 1,732,700 issued Oct. 12, 1925, to Sommer et al describes a series of machining units that are mounted on a rotary turret to travel in an endless path, where each of the machining units moves past the operator's station. As each of the units moves past the operator's station the operator removes the finished workpiece or article and inserts a blank or unfinished workpiece onto a shaft or chuck. The machining of each blank occurs during the rotation of that individual machining unit about the endless path.
In more detail, the Sommer's patent comprises a base with a post attached at the center thereof, where the series of machining units are mounted about the post and suspended downward therefrom. Each workpiece, which is shown as a spindle, is inserted into a tapered socket chuck so that it can be machined. The machining occurs during the rotation of the turret relative to an annular cam track which rises throughout the rotation. The cam controls moving the workpiece into and out of contact with the cutter. At the point where the operator loads and unloads the workpieces, the annular cam track has a depressed portion such that the finished workpiece can be removed from the cutter and a new blank or unfinished workpiece can be inserted. The machining action in the Sommer invention is dependent upon the rotation of the machining device on the annular cam track such that the workpiece will be initially forced into contact with the cutter at a shoulder and movement of the workpiece results from the contour of the annular cam track, which completes the machining action. Thus, the workpiece can not be machined without rotation of the machining tool relative to the annular cam track.